Combination steering, clutch, and throttle control



July 14, 1953 G. L. TURNER ET AL COMBINATION STEERING, CLUTCH, AND THROTTLE CONTROL Filed Sept. 16, 1949 16 Sheets-Sheet l INVENTOR.

GEORGE L. TURNER ROBERT LAPSLEY fizxfl 7 ATTY.

July 14, 1953 a. L. TURNER ETAL COMBINATION STEERING, CLUTCH, AND THROTTLE CONTROL Filed Sept. 16, 1949 16 Sheets-Sheet 2 FIG. 2

INVENTOR. GEORGE 1.. TURNER ROBERT LAPSLEY dam ATTY.

July 14, 1953 G. L. TURNER ETAL 2 6 COMBINATION STEERING, CLUTCH, AND THROTTLE CONTROL Filed Sept. 16, 1949 16 Sheets-Sheet 3 T .INVENTOR. GEORGE L. TURNER ROBERT LAPSLEY ATTY July 14, 1953 G. 1.. TURNER ETAL COMBINATION STEERING, CLUTCH, AND THROTTLE CONTROL Filed Sept. 16, 1949 16 Sheets-Sheet 4 INVENTOR.

GEORGE L. TURNER ROBERT LAPSLEY FML) ATTY.

ma \N 8 om mm 5 July 14, 1953 G. TURNER EIAL COMBINATION STEERING, CLUTCH, AND THROTTLE CONTROL Filed Sept. 16, 1949 v 16 Sheets-Sheet 5 INVENTOR. L.TURNER ROBERT LAPSLEY ATTY.

Jul 14, 1953 s. 1.. TURNER ETAL 2,645,

COMBINATION STEERING, CLUTCH, AND THROTTLE CONTROL Filed Sept. 16, 1949 16 SheetsSheet 6 INVENTOR. GEORGE L. TURNER ROBERT LAPSLEY July 14, 1953 s. L. TURNER ET AL COMBINATION- STEERING, CLUTCH, AND THROTTLE CONTROL Filed Sept. 16, 1949 16 Sheets-Sheet '7 FIG. 7

INVENTOR. GEORGE L. TURNER BY ROBERT LAPSLEY ATTY.

July 14, 1953 G. 1.. TURNER ETAL 2,645,296

COMBINATION STEERING, CLUTCH, AND THROTTLE CONTROL Filed Sept. 16, 1949 16 Sheets-Sheet 8 FIG. 9

IN VENTOR. GEORGE, L. TURNER BY ROBERT LAP$LEY ATTY.

July 14, 1953 s. L. TURNER ETAL COMBINATION STEERING, CLUTCH, AND THROTTLE CONTROL Filed Sept. 16. 1949 16 Sheets-Sheet 9 ATTY.

IN VEN TOR.

GEORGE L. TURNER ROBERT LAPSLEY July 14, 1953 G. L. TURNER ETAL' COMBINATION STEERING, CLUTCH, AND THROTTLE CONTROL Filed Sept. 16, 1949 16 Sheets-Sheet 10 INVENTOR. GEORGE L. TURNER ROBERT LAPSLEY M ATTY.

y 14, 1953 GJL. TURNER ETAL 96 COMBINATION STEERING, CLUTCH, AND THROTTLE CONTROL Filed Sept. 16, 1949 16 Sheets$heet 11L IN VENTOR. GEORGE L. TURNER ROBERT LAPSLEY y 14, 1953 a. L. TURNER ETAL 2,645,295

COMBINATION STEERING, CLUTCH, AND THROTTLE CONTROL Filed Sept. 16, 1949 16 Sheets-Sheet 12 FIG. I5

GEORGE L. URNER BY ROBERT LAPSLEY M ATTY.

July 14, 1953 G L. TURNER E A]. 2,645,296

COMBINATION STEERING, CLUTCH, AND THROTTLE CONTROL Filed Sept. 16, 1949 16 Sheets-Sheet 1:5

FIG. 16

INVENTORQ GEORGE L. TURNER ROBERT LAPSLEY fggm ATTY.

y 14, 1953 G. L. TURNER ETAL 2,645,296

COMBINA ION STEERING, CLUTCH, AND THROTTLE CONTROL FIG. I7

MANUAL SELECTION FOR FORWARD & REVERSE INVENTOR. GEORGE L. TURNER ROBERT LAPSLEY Y M m r M ATTY.

y 4, 1953 e. L. TURNER ETAL 2,645, 96

' COMBINATION STEERING, CLUTCH, AND THROTTLE CONTROL Filed Sept. 16, 1949 16 Sheets-Sheet 16 FIG. I9

INVENTOR. GEORGE L. TURNER ROBERT LAPSLEY ATTY.

Patented July 14, 1953 i t i COMBINATION STEERING, ,CIIUTCH,

THROTTLE CONTROL eND George L. Turner and Robert Lapsley, Buchanan,

Mich, assignorsto Clark Equipment Company, Buchanan, Mich., a corporation of Michigan Application September 16, 1949, Serial No. 115,982

'10 Claims. 1

Our invention rel-ates to industrial lift trucks and is more particularly directed to an industrial lifttruck adapted for lifting, transporting, stacking and depositing relatively heavy loads.

Heretofore, it has been difiicultto provide a conventional form of industrial lift truck which would handle relatively heavy loads and still maintain good maneuverability over a wide range of operating conditions.

It is an object of our present invention to provide an industrial lift truck having a pair of forward driving wheels with two individual prime movers or power plants, which may, for example, be internal combustion engines, of which one each is connected by suitable drive means to one each of theforward driving wheels. By providing each forward wheel with its own individual. drive, the truck is capable of pivoting about a point located between the drive wheels when the wheels are driven in opposite directions with respect to each other. The truck may thus be easily maneuvered in confined areas.

It is another object of our present invention to provide each of the drive means of the aforementioned prime movers with clutch means,

which means comprises a pair of clutches, one for effecting forward drive and the other for effecting reverse drive of the drive wheels.

The prime movers may be connected through the drive means to the forward wheels for forward rotation of the same by actuating the forward drive clutches, and the primemovers may be connected to the forward wheels for reverse rotation of the same by actuating the reverse drive clutches.

It is a further object of our present invention to provide a multi-speed planetary transmission for each of the aforementioned prime movers for effecting selectively substantially the same speeds in both forward and reverse drives toeach drive wheel.

It is a still further object of our invention to provide a control system for independently and automatically regulating the speed of each prime mover and for governing the direction of the drive to each forward wheel in response to rotary movement of the steering wheel.

We propose the accomplish the last aforesaid object by providing the steering wheel with a draw. rod that is adapted to be moved rectilinearly in response to rotary movement Ofthe steering wheel. Mounted atthe end of the draw rodiis each prime mover or power plant comprises an 2 internal combustion engine which is controlled by a throttle. The cam follower has connection to the throttles of each engine. The control system is arranged between the steering wheel and the throttle of-eachengine in a manner which permits the throttles to open and close in unison when the throttle pedal of the truck is actuated and the truck is following a substantially straight line in either a forward or backward direction, and which, if the throttle pedal of the truck is kept constant, will, When turning of the truck is initiated to the right, cause the throttle of the engine adjacent the right side of the truck to be reduced, and when turning of the truck is initiated-to the left, cause the throttle of the engine adjacent the left side of the truck to be reduced; By virtue of this arrangement, the engines are utilized during a steering; maneuver for reducing the effort that must be exerted by the driver in turning the truck.

As the turning radius to the right is decreased, the throttle is reduced until the idle throttle conditionof theengine is reached, at which time the aforementioned cam actuatesa switch eonnected to the forward drive clutch of the right engine for electrically deenergizing the same; If the turning radius is still further reduced the cam is adapted to actuate a switch connected to the reverse drive clutch of the right engine for energizing the same. As the right drive wheel be-.

gins to rotate in reverse, the cam, by means. of

the follower, actuates the throttle for the right engine increasing it from idle to full throttle position. Both wheel are thus rotated under full throttle conditions in. opposite directions which effects rotation of the truck about a point midway between the drive wheels.

When it is desired to back the truck up following a path similar to thatfollowed while driv ing the truck forward a remote control provided for the operator need only be shifted from its forward position to its reverseposition, at which time the control system will perform the sequence of operations, as outlined above in reverse.

.A still further- .object of our invention is to provide arear support means for the truck com-, prising a pair of wheels one each disposed adjacent each side-of a vertically extending rotatable shaft and rotatably mounted one each to each end of a supporting frame disposed adjacent the lower end of the shaft, which supporting frame is mounted for limited rotation about a horizontal axis extending transversely of and belowthe axesofthe wheels.

A still further object of our invention is to provide a steering mechanism for effecting rotative movement of the steering wheel, for the operator, into rotative movement, of at least 180, of the rear wheels of the truck by means of a substantially rectilinearly movable member connected between the steering wheel disposed at the forward end of the truck and the rear wheels of the truck.

Now in order to acquaint those skilled in the art with the manner of constructing and using industrial trucks embodying the principles of our present invention, we shall describe in connection with the accompanying drawings, a preferred embodiment of our invention.

In the drawings: a Figure 1 is a front perspective view of an industrial truck constructed in accordance with our present invention;

Figure 2 is a plan view, largely diagrammatic,

Figure 5 is a sectional view of one of the transmissions for one of the prime movers taken sub-' stantially along a horizontal plane passing through the drive and driven shafts of the transmission showing the connection between the drive shaft of the transmission and the output shaft of one of the clutch means of Figure 4;

Figure v6 is a vertical sectional view taken substantially along line 6- -5 of Figure 5 looking in the direction indicated by the arrows and showing brake means for the transmission;

Figure '7 is a sectional view of oneof the brake means of Figure 6 taken substantially along a vertical plane extending transversely of the axes of the input and output shafts of the transmission;

Figure 8 is a horizontal sectional view of the dual axle drive means of our present invention taken substantially along a horizontal plane passing through the drive axles of the truck;

Figure 9 is a partial front elevational view of the dual axle drive means of Figure 8 with the front cover member removed;

Figure 10 is a side elevational view of the truck shown in F gure 1;.

Figure 11 is a vertical sectional view with cercontrol means taken substantially along the linel4|4 of Figure 12 looking in the direction of the arrows;

Figure 15 is a verticalsectional view of the control means taken substantially along the line l5--I5 of Figure 12 looking in the direction of the arrows; a

Figure 16 is a horizontal sectional view of the control means taken along the line 6-46 of Figure 15 looking in the direction of the arrows;

' the latter by the channels l'I-|1.

Figure 171s a circuit diagram of the electrical connection between the several switches of the control means shown in Figure 16;

Figure 18 is a chart showing the relationship between the forward and reverse drive electric clutches, the throttles of each engine, and the switches of the controlmeans corresponding to various selected driving conditions; and

Figure 19 is a diagrammatic view of the hydraulic control system embodied in the truck of Figure 1.

General arrangement of truck Referring now to Figures 1 and 2 there is shown an industrial truck indicated generally by the reference numeral 25. As previously indicated the truck primarily is adapted for handling heavy loads of the order of 15,000 lbs. The truck comprises a main frame 26, shown in detail in Figure 3, having a pair of spaced apart lengthwise extending main side frame members 21 and 28 at the forward ends of which, cap members 27 and 28 are secured and which cap members and forward ends of the frames are formed to define openings for receiving the axle housing arms of a drive axle assembly to be described. The frame 26 further comprises a forward transverse platform frame member 3! having a recess 32 formed therein providing for the support of the cylinder of the hydraulic cylinder and piston assembly 50, and a rear transverse frame member 33 having an aperture 34 formed therein in which a steering shaft 202, shown in Figure 11, is adapted to be journalled. The frame further comprises a pair of upper parallel channels l2-l2 extending between'the end frame 33 and, an intermediate transverse channel [3 supportedby post channel members I4--|4. The area defined by the channels last described provides for the mounting of the prime movers of the truck to be described. Av second pair of spaced lengthwise extending channel frame members IB lie laterally outwardly of the frame members 2] and Z8 and are connected at their forward ends to The frame is completed by a transverse channel 18 to which the rear ends of the side frames 21 and 28 are secured as by welding, and the ends of channel [8 in turn, are secured as by welding, to the channels [6. The frame is enclosed by suitable panel members preferably of rather heavy gauge to add weight to the truck to counterbalance a load adapted. to be supported forwardly of the truck. As shown in Figure 1, the drivers seat and controls for. the truck are positioned forwardly of the. engine compartment.

Referringagain to Figures 1 and 2, the industrial truck 25, as shown, is provided with a pair of dual forward drive wheels 3535 and 36-36 which are adapted to be driven by a pair of prime movers 3i and 3% which in the present embodiment are internal combustion engines. The engines are provided with a. conventional ignition system, starting motors, cooling means, fuel supply means, and the other ancillary known devices for effecting their operation. Interposed between the prime movers 3i and 33 and their associated dual drive wheels 3535 and 36-36 are a pair of clutch means indicated generally at 3:9 and 40 for providing forward and reverse drives, a pair of transmissions enclosed with a unitary housing and indicated generally at M and 42 for providing a plurality of substantially equal forward and reverse speed ratios to the drive wheels, and dual axle drive means indicated generally at 43. The construction of the above several elements of truck will be described in detail hereinafter.

The truck 25 is further provided adjacent its rear end with a steering wheel assembly indicated generally at 44, and adjacent its forward end is provided with a vertically extending mast indicated at comprising pairs of spaced apart channel members 46-46 and in which second channels 41-41 are telescopically arranged. The members 46-46 are interconnected by a pair of U-shaped braces 48 and 49. The channel members are adapted to be moved vertically by means of a hydraulic piston and cylinder assembly 50 which is centered between the channel members 4|4'|. Mounted adjacent the front of the truck to the members 41-41 there is shown a load supporting carriage which is fully described in the copending application of George L. Turner, one of the present joint inventors, Serial No. 115,397, filed September 13,

1949, now Patent No. 2,608,315, granted August 25, 952. Secured to the front of the load supporting carriage are a pair of box-like frame members 5| and 52 which extend transversely forwardly of the truck. A pair of forks 53 and 54 are provided adjacent the forward end of the truck and are loosely supported by the upper box-like frame member 5|. For purposes of our present invention the mast and load supporting carriage may be of any of the presently known conventional types. Since our present invention is not concerned per se with such structures, it 'is believed a further description thereof is unnecessary for purposes of this disclosure.

Clutch means for forward and reverse drives Referring now to Figure 4, there is shown the clutch means 39 and 49 for effecting forward and reverse drives for the truck. The clutch means 39 and 49 each comprise two eddy current type clutches, more commonly known as electro-dynamic clutches, which are arranged coaxially in end to end axial spaced relation, and which are selectively controllable through suitable switch means, so that the operator may select either one or the other clutch for operation. These clutches, a pair of which are associated with each prime mover 31 and 38, the prime movers through suitable transmission means 4| and 42 to the dual axle drive means 43. The operator, through a suitable control lever, may select one of a plurality of speeds simultaneously of both of the transmission means 4| and 42, irrespective of whether forward or reverse drive through the electric clutches is selected.

By the provision of electro-dynamic clutches, we eliminate wear and replacement diificulties heretofore encountered in connection with vehicles of this type, due to the heavy service placed upon clutches of such vehicles in normal operation. There is no frictional contact in the present clutch construction and, consequently, there is no wearing of parts.

Furthermore, electro-dynamic clutches of the present construction may be controlled by a switch or a clutch pedal, and may be selectively operable to increase or decrease the slippage through the clutch for regulating the transmission of torque from the prime movers 3'! and 38 to the transmission means 4| and 42. This, in effect, is the same as the slippage of a friction clutch, but does not offer the disadvantages of are adapted to transmit torque. from a construction of this type, since there are no frictionally contacting parts. For purposes of the present disclosure, it is believed that a detailed description and showing of the clutch means 39 will be sufficient since the clutch means 39 and 40 are of identical construction.

The clutch means 39 comprises a housing 55, which may be secured in a known manner to the flywheel housing of the prime mover 31 (not shown in this view) having a crankshaft 56. Bolted or otherwise suitably secured to the crankshaft 56 is a flange member 51, having a hub portion 58 which is suitably bored to receive a ball bearing assembly 59 for journalling the reduced end 60 of the main clutch shaft. 6| therein. The shaft 6| is journalled adjacent its other end in a 'ball bearing assembly which is disposed within the rear end wall of the housing 55. Secured to the outer peripheral edge of the flange member 51 is a rotatable housing indicated at 62. This rotatable housing 62 comprises two annular flywheel casings 63 and 64;

preferably joined together, as indicated at 65, by

welding or the like, which casings carry enclosed therein magnetic cores or field windings 66 and 61, respectively. The flywheel casings are preferably provided with air passages, such as at 68 and 69 for dissipating the heat generated within the magnetic cores 66 and 61 when the coils are being electrically energized.

casing 63 which tends to attract the pole piece- 12 for conjoint rotation therewith. The amount of current introduced into the core 66 effects control of the magnetic field and determines the amount of slippage that will take place between the flywheel casing 63 and the pole piece 12.

A sleeve member 13 is journalled at one end thereof on the hub portion 14 of the rotor member II by means of a ball bearing assembly 15. The sleeve member 13 adjacent its other end is journalled between the main portion of the shaft 6| and a ball bearing assembly '19 in a plate member 18 mounted on the housing 55. The rotatable housing 62 is journalled adjacent its free end on the sleeve member 13 by means of a ball bearing assembly 26.

A second rotor 16 is suitably secured to the sleeve member I3 intermediate the ends thereof and the rotor 16 carries an annular pole piece 11 adjacent the outer periphery thereof. The pole piece 11 is of substantially the same axial extent as the inner surface of the flywheel casing 64 and there is also a small but uniform air gap maintained therebetween.

Upon energization of the core 61 an eddy current is set up within the flywheel casing 64 which tends to attract the pole piece I! for conjoint rotation therewith.

Mounted to the outer end of the sleeve member 13 is a gear 2| which is adapted to have mesh.- ing engagement with an idler gear 88 which in turn has meshing engagement with a gear 60 of a dual gear 9| carried on the transmission input'shaft al shownv in dotted lines; Secured to a reduced portion 82 of the clutch shaft 6! is av gear 83 which is adapted. to have meshing engagement with gear 84 of the dual gear 94, on the aforementioned transmission input shaft SI.

When it is desired to drive wheels 35i' 5 in a forward direction coil 61 is energized which causes the rotor member It to rotate conjointly with the flywheel casing 64, thus causing gear 21 to drive idler gear 88 which in turn drives the gear 80 on the transmission shaft 8|. When it is desired to reverse the drive. of wheels 35, coil 6'I'is deenergized' and coil 66 energized. This causes the rotor member I! to rotate conjointly with the flywheel casing 63, thus causing the main clutch shaft 6! to rotate, which drives gear 83 and in turn gear 34 'of the transmission shaft 8|. This efiects reverse rotation of the trans-- mission. shaft 8! with respect to the main clutch shaft BI.

s In a manner similar to that described above but by the reverse energization of the coils of ill the clutches, clutch means Ed may be selectively actuated to effect driving of the wheels Sit-43';

' either forwardly or rearwardly. In other words,

energization of coil t! of clutch means at eifects reverse drive of wheels 33-456, while de-energization of coil 6? andenergization of coil 56 drives the wheels 3fi33 forwardly. A. pair of clutches are provided for each pair of forward drive wheels so that they may be clutched independently of each other.

Planetary gear transmissions We further propose to provide the industrial truck of our present invention with a pair of planetary gear transmissions 4i and 12 for effecting a plurality of drive ratios between the drive and driven shafts of the transmission. Planetary transmission means are particularly desirtion, it is believed that a detailed showing and description of one will be sufiicient for the purposes of the present disclosure. The transmission means 4| is disposed within a housing 98 which is suitably secured at its one rear end in a known manner, as by bolts, to the front end of the clutch housing and at its front end to the housing provided for the dual axle drive means 43 which will be fully described hereinafter.

Disposed lengthwise within the transmission housing 95 in end to end co-axial spaced relation are a drive shaft SI and a driven shaft 52. The drive shaft 8| is journalled adjacent one end thereof in a ball bearing assembly 93 mounted in a bearing supporting member 93' mounted inwardly of the rear end of the transmission housing 90. The other end of the drive shaft 8| has an integral flange member 94 the purpose of which will be hereinafter described. Secured adjacent the periphery of the flange member 94 is a planet carrier 95 which carries planet pinion laterally projecting sleeve I04.

means 95, including'multiple integral coaxially arranged planet pinions ill, 98, 99 and NB.

The transmission housing is provided adjacent its rear end with an inwardly extending flange member IIlI having a laterally projecting annular flange I02 formed integrally therewith. The housing 90 is further provided intermediate its ends with an inwardly extending flange member I03 having a first laterally projecting annular flange member I04 secured as by bolts thereto.

Rotatably mounted on the drive shaft BI is a first sleeve member I05 having secured adjacent its forward end a first reaction pinion I40 which is adapted to have meshing engagement with the planet pinion 98 of the planet pinion means 96. Adjacent the other end of the sleeve member I05 is secured a brake drum I06 having a rim portion I0? and an intermediate laterally projecting annular flange I08 which is adapted to be journalled on the laterally projecting annular flange I82 of the flange member IDI.

Rotatably mounted on the first sleeve member I05 is a second sleeve member Hi9 having secured adjacent its forward end a second reaction pinion I It which has meshing engagement with the planet pinion 9'! of the planet pinion means 96.

The second sleeve member I69 adjacent its other.

or rear end is journalled between the inner peripheral surface of the lateral annular projection I62 of the inwardly extending flange member ID I and the outer peripheral surface of the first sleeve member I 05. Secured to the second sleeve member I05 intermediate its ends is a second brake drum Iii having a rim portion H2.

The driven shaft 92' is journalled adjacent its forward end within a pair of roller bearing assemblies H3 and H4 which are mounted in the forward end wall of the transmission housing Bil. Secured to the other end of the driven shaft 92 is a sun gear I i 5, which has meshing engage ment with the pinion 99 of the planet pinion means 96. Journalled on the hub portion IIB of the sun gear H5 is the enlarged portion I I I of a stepped sleeve member I I8, which is secured to the planet carrier 95. The reduced forward end portion I I9 of the stepped sleeve member I I8 is journalled in pin bearings disposed between it and the inner peripheral surface of the annular Journalled on the outer peripheral surface of the member I04 is the laterally projecting annular flange I20 of a third brake drum I 2i having a rim portion I23. Mounted to the brake drum IZi', as by bolts, is a second laterally projecting annular flange member I22 which is journalled on the intermediate portion I I! of the stepped sleeve member I I8. The flange member 522 adjacent its outwardly projecting end has a pinion I ii secured thereto which is adapted to have meshing engagement with the pinion I69 of the planet pinion means 95.

Cooperating with the rim portion It? of the brake drum I66 is a brake band 524, which is adapted to be selectively actuated by brake actuating means at I28, for braking the brake drum I06 against rotation. Cooperating with the rim portion I I2 of the brake drums MI is a brake band I25 which is adapted to be selectively actuated by brake actuating means, indicated at E29, for braking the brake drum I I I against rotation. Cooperating with the rim portion I23 of the brake drum I2I are a pair of brake bands I26 and I2'I, which are adapted to be selectively actuated conjointly by brake actuating means, indicated at 

